Comparison of observed lung retention and urinary excretion of thorium workers and members of the public in India with the values predicted by the icrp biokinetic model

• Published in: Radiation protection dosimetry Vol. 112; no. 2; pp. 237 - 243
• Main Authors: Jaiswal, D. D., Singh, I. S., Nair, Suma, Dang, H. S., Garg, S. P., Pradhan, A. S.
• Format: Journal Article
• Language: English
• Published: England Oxford University Press 2004
• Subjects: Adolescent; Adult; Body Burden; Child; Computer Simulation; Food Contamination, Radioactive - analysis; Guidelines as Topic; Humans; India; Internationality; Kinetics; Lung - metabolism; Metabolic Clearance Rate; Models, Biological; Nuclear Reactors; Occupational Exposure - analysis; Organ Specificity; Radioactive Pollutants - analysis; Radioactive Pollutants - pharmacokinetics; Radiometry - methods; Radiometry - standards; Reproducibility of Results; Risk Assessment - methods; Risk Assessment - standards; Risk Factors; Sensitivity and Specificity; Thorium - analysis; Thorium - pharmacokinetics; Thorium - urine; India
• ISSN: 0144-8420; 1742-3406
• DOI: 10.1093/rpd/nch390

The daily intake of natural Th and its contents in lungs, skeleton and liver of an Indian adult population group were estimated using radiochemical neutron activation analysis (RNAA) technique. These data on daily intake (through inhalation and ingestion) were used to compute Th contents in lungs and other systemic organs such as skeleton and liver using the new human respiratory tract model (HRTM) and the new biokinetic model of Th. The theoretically computed Th contents in lungs, skeleton and liver of an average Indian adult are 2.56, 4.00 and 0.17 μg, respectively which are comparable with the corresponding experimentally measured values of 4.31, 3.45 and 0.14 μg in an urban population group living in Mumbai. The measured lung contents of Th in a group of five occupational workers were used to compute their total body Th contents and the corresponding daily urinary excretions. The computed total body contents and daily urinary excretions of Th in the five subjects compared favourably with their measured values. These studies, thus, validate the new biokinetic model of Th in natural as well as in occupational exposures in Indian conditions.